Frozen pipes at rental

[Elijah White]

My tenant called me this morning to tell me that the hot water is not coming out of the faucet and he thinks that the line might be frozen. He left the cold water dripping overnight so that is still working but he didn't leave the hot water dripping. I contacted my plumber but they are so busy with frozen pipe calls that they won't be able to get out to the property for 3 days. My tenant is able to use his partner's place to shower for the next couple days so that's good, but is there anything I should be doing in the meantime until the plumber comes out to the property? I live 4.5 hours away or else I would try to thaw the pipe myself. Additionally, the hardware stores in the area are sold out of pipe insulation and heating tape so I'm not sure what else I would even do if I were close by aside from trying to thaw it with a blow dryer. 

Thanks in advance for the advice!